Beginner. AD hash crack (min 12 char)

[Snoopy]

i think the hahscat wiki is a very good first spot to take a look

to achieve the things you mentioned there are 2 main possiblities, hashcat supports combining two wordlist, known as combinator attack, so you can use your first wordlist and generate a second one like this

hashcat --stdout -a 3 19?d?d
or with maskprocessor from hashcat tools see https://hashcat.net/wiki/doku.php?id=hashcat_utils

this will generate all numbers from 1900 to 1999 (unsorted) you can redirect or use -o to get this this to a file and have a simple second word list, with combinator attack -a 1 this would result in combining all passwords from your wordlist with all numbers from 1900-1999

the same would be possible with rules, attack mode -a 0

sample rule
$1 $9 $0 $0
meaning append 1 append 9 append 0 append 0 to every word in wordlist, put this into a file named rule.txt put a password in a file called pw.txt run hashcat like this and you will see the "generated" password with 1900 appended

hashcat --stdout -a 0 -r rule.txt pw.txt

for all rules see
https://hashcat.net/wiki/doku.php?id=rule_based_attack
or take a look into the rules folder, there are some basic rulesets like best64.rule

for basic attacks refer to hashcat --help ot wiki

  Wordlist + Rules hashcat -a 0 -m hashtype hashfile wordlist -r best64.rule
  Brute-Force hashcat -a 3 -m hashtype hashfile ?a?a?a?a?a?a
  Combinator hashcat -a 1 -m 0 hashtype wordlist1 wordlsit2